Medications have cured many sick people. However, medications when combined with certain foods have made many healthy people sick.
Some foods decrease the absorption of drugs in the body and make them less effective, because not enough drugs get into the blood stream. On the other hand, certain foods can interfere with the excretion of drugs increasing the amount of them in the body. The more drugs in the system, the greater the possibility of toxic side reactions.
Both of the above situations can cause worrisome side effects. Consider the following example:
Renee is a 38 y/o vegetarian being treated as an outpatient because of irregular heart rhythms (atrial fibrillation). She routinely takes an anticoagulant, a medication used to “thin” the blood. Her diet consists mainly of fruits and vegetables. .
One evening she was rushed to the ER after complaining of a headache, being anxious, tired, dizzy and experiencing shortness of breath. Laboratory tests indicated that her blood results were outside the desired anticoagulant target range. The medication wasn’t working. Her blood was “too thick,” a precursor to the formation of blood clots and the potential that these clots might break away causing damage to the lungs or brain.
An electrocardiogram indicated she was having “runs” of atrial fibrillation. She needed intravenous medications to reverse these abnormal heart rhythms and prevent the possibility of a stroke. Her anticoagulation medicine was adjusted to achieve the desired target range. However, her chest X-ray (CT) indicated she had suffered a pulmonary embolus (see below). What follows are examples of food-drug interactions:
Food — Drug Interactions
Grapefruit Juice
Grapefruit juice interacts unfavorably with many types of drugs. Ordinarily, the body uses a special enzyme (see below) to break down the composition of drugs so that they can be eliminated from the body. Grapefruit juice works against this enzyme causing the accumulation of drugs in the body with potential dangerous side effects
For example, patients taking Lipitor (lowers cholesterol in the blood) and grapefruit juice might experience a build-up of this drug in the body causing liver problems, muscle pain and weakness. Those taking certain medications for hypertension, especially in the elderly, might experience lightheadedness and fainting spells because of a sudden drop in the blood pressure when standing up.
Adverse side effects have been reported with oral contraceptive, viagra, and valium like medicines. The list of grapefruit juice interaction with drugs is a long one. If you take medication, especially on a long term basis, it’s probably best to eliminate grapefruit juice from your diet.
Green Leafy Vegetables
Vitamin K is important for blood coagulation. In certain clinical conditions (atrial fibrillation, heart valve patients), it’s beneficial to use anticoagulants (blood thinners) to minimize the likelihood of the formation of blood clots, emboli and a stroke.
The anticoagulant Coumadin (warfarin) interferes with vitamin K. It prolongs the bleeding time and works to prevent clot formation — thrombosis.
Renee, noted above, was eating a lot of green leafy vegetables, a good source of vitamin K (kale, Brussels sprouts, salad vegetables). High levels of vitamin K in her diet interfered with the effectiveness of Coumadin causing cardiac and pulmonary (embolus) emergencies necessitating a trip to the E.R.
Tyramine Containing Foods
Tyramine is a chemical found naturally in the body and in foods. It helps regulate blood pressure. Eating foods high in tyramine while taking certain medication for depression can trigger a hypertensive crisis — a dangerous increase in blood pressure. Also of note, foods with tyramine can provoke migraine headaches.
Tyramine is found in many foods and drinks:
- Aged cheeses
- Chocolate
- Red wine, beer
- Smoked fish
- Processed meats (hot dogs, bacon, salami)
- Leftover foods (foods past their freshness)
It was first isolated from cheese and later named after the Greek (tyros) for cheese. Several drugs interfere with the breakdown of tyramine, including some prescribed for Parkinson’s disease and depression (MAOIs — see below).
Dairy Products
Dairy products can block the effectiveness of antibiotics when both are taken at the same time. The calcium in these products binds to the antibiotic in the stomach or small intestine. This combination delays or prevents antibiotics, such as tetracycline or Cipro, being absorbed into the body. As a useful rule, separate dairy products and the interacting drug by at least two to four hours. To minimize the likelihood of an upset stomach, some antibiotics are taken with food.
Alcohol
The interaction of alcohol with certain medications can be dangerous. Although not a food per se, the sedating effects of mixing alcohol with drugs deserve special mention.
People who jointly take medicines such as antihistamines, muscle relaxants, narcotics and antidepressants with alcohol are at an increase the risk for serious side effects. Women and older people face greater risks with the mixing of alcohol and drugs.
This potentially deadly combination has caused drowsiness, dizziness, rapid heart rate, uncoordinated movements, and difficulty breathing. Falls, injuries and accidents have resulted because of this dangerous combo.
Adverse drug reactions happen every day. To minimize side effects, inform your doctor and pharmacist about herbal products, vitamin — mineral supplements, over the counter medications or other products you might be taking. Also, of course, read the printout the pharmacist gives you when you pick up the prescription.
Glossary
An enzyme (CYP3A4) is used by the body to break down the composition of drugs. Grapefruit juice contains a class of chemical compounds called furocoumarins that inhibit intestinal CYP3A4.
Embolus is an unattached mass, for example, a blood clot that has broken away from its point of origin and travelled through the bloodstream to lodge in a distant site such as the lung
MAOIs inhibit the activity of the enzyme monoamine oxidase. This action prevents the breakdown of monoamine neurotransmitters and thereby increasing their availability.
References
Bailey, David G et al; Grapefruit Juice—drug interactions Br J Clin Pharmacol, Aug. 1998
McCabe, BJ; Prevention of Food-Drug Interactions with Special Emphasis on Older Adults; Curr. Opin. Clin. Metab. Care; Jan.7, 2004
Bobroff, Linda B. et al’ Food/Drug and Drug/Nutrien Interactions; Univ. Florida, May, 2009
NIH; Harmful Interactions: Mixing Alcohol With Medicine; No 13-5329, 2003-revised 2014
This article is intended solely as a learning experience. Please consult your physician for diagnostic and treatment options.